Speaking from England's St George's Park base, Oxlade-Chamberlain said: "I'm delighted to have signed for Liverpool and a big thank you to everyone here at the FA that has made this possible, using the facilities. It has been a massive help.

"I'm not going to say too much. I'm here with England and we've got two big games coming up, so I want to focus on them. But I can't wait to get to Melwood."

A post on his Instagram page, addressed to Arsenal fans, read: "After six years, three FA Cup wins and countless incredible memories, the time has come for me to move on from Arsenal.

"I want to publicly thank Arsene Wenger, the coaching and club staff and my amazing team mates for all of the incredible opportunities I have been given. Thank you so much to you, the fans, who have always had my back - I honestly couldn't be more grateful. The club, and my time here, will always mean a massive amount to me.

"I know my choice might come as a surprise to many, and the decision to leave was tough after being a part of the club for so many years, but I feel that this move is right for the next stage in my ongoing development."

Oxlade-Chamberlain was used at wing-back in his final few months at Arsenal, and his desire to establish himself in central midfield was a motivating factor in his departure.

Jurgen Klopp told the Liverpool website: "I hear a lot of talk about positions but let's talk about the player; he is someone with really good abilities who always gives everything for his team. A player that is positive and willing to take risks to try and make positive things happen.

"He may still be young but he has a lot of experience in the Premier League, Champions League and for his country. Already he is a very, very good player and I think he has the mentality and desire to get even better - and that excites me.

"I am really, really happy we have got Alex signed. Since the last game I have been waiting and hoping we could make this transfer - and when I got the news he was ours it was fantastic."

Alex Oxlade-Chamberlain trains with England ahead of their World Cup Qualifiers

Alex Oxlade-Chamberlain trains with England ahead of their World Cup Qualifiers

Oxlade-Chamberlain's final game of a six-year spell at Arsenal came at Anfield on Sunday as he was part of a side beaten 4-0 by Klopp's Reds.